University of Wisconsin–Madison

Ultra-low Dose Body Computed Tomography (CT)

June 2011 to March 2013

The primary goal of this project is to develop and clinically validate novel methods for computed tomography (CT) image reconstruction and display that would allow for substantially reduced radiation dose and possibly even improved image quality over current methods. These newer algorithms, such as “prior image constrained compressed sensing” (PICCS) and “model-based iterative reconstruction” (MBIR) have the potential to create diagnostic CT images using a scan obtained at a small fraction of the dose required for the current CT reconstruction algorithm of “filtered back projection” (FBP). To validate these new methods, we require an ultra-low dose CT scan series (i.e., obtained a dose level that would result in unacceptable image quality using current reconstruction methods – generally an order of magnitude less dose) that can be directly compared side-by-side against a standard routine dose CT scan series in the same patient. If objective and subjective image quality obtained using these novel reconstruction algorithms with an ultra-low-dose acquisition is the same or better compared with the current protocols using standard dose and FBP reconstruction, we hope to efficiently validate and implement these techniques into our routine practice. If successful, this would result in an immediate and substantial reduction in dose to all patients undergoing body CT scanning – probably on the order of a ten-fold decrease in dose.

This project led by: Perry J Pickhardt, MD